Practice TEAS Science Test

Correct Answer: B

Rationale: The correct answer is B: Hypothalamus. The hypothalamus is responsible for maintaining homeostasis in the body by regulating various bodily functions such as body temperature, thirst, hunger, sleep, and hormonal balance. It receives input from different parts of the body and initiates responses to maintain internal stability. The brainstem (A) is involved in basic life functions like breathing and heart rate but does not play a direct role in homeostasis. The medulla oblongata (C) controls involuntary functions like breathing and swallowing. The cerebrum (D) is responsible for higher brain functions like thinking and voluntary movements, not for maintaining homeostasis.

Correct Answer: C

Rationale: The correct answer is C: Nucleus. The nucleus contains the cell's genetic material in the form of DNA, which carries the instructions for the cell's functions and characteristics. This is where processes such as transcription and replication occur. Ribosomes (choice A) are responsible for protein synthesis. Mitochondria (choice B) are the powerhouse of the cell, producing energy. Cytoplasm (choice D) is the fluid that fills the cell and supports organelles, but it does not store genetic information.

Correct Answer: B

Rationale: The correct answer is B: Medulla oblongata. The medulla oblongata, located in the brainstem, controls essential functions like breathing and heart rate. It contains centers that regulate these automatic processes. The cerebrum (A) is responsible for higher brain functions, not controlling basic physiological functions. The thalamus (C) serves as a relay station for sensory information, not for regulating breathing and heart rate. The cerebellum (D) plays a role in coordination and movement, not in controlling vital functions like breathing and heart rate.

Correct Answer: B

Rationale: The correct answer is B: Larynx. The voice box, also known as the larynx, is responsible for producing sound by manipulating airflow from the lungs. The other choices are incorrect because: A: Alveoli are small air sacs in the lungs for gas exchange. C: Trachea is the windpipe that carries air to and from the lungs. D: Pharynx is the throat region where the nasal and oral cavities meet.

Correct Answer: D

Rationale: The correct answer is D because the Vas Deferens connects each testis to the urethra, allowing sperm to travel from the testes to the urethra during ejaculation. This tube plays a crucial role in the male reproductive system by transporting sperm for ejaculation. A is incorrect because the production of fluid to increase sperm mobility is carried out by the seminal vesicles and prostate gland. B is incorrect because the site where the egg matures is the fallopian tubes in females. C is incorrect because controlling urine flow is the function of the urethra and muscles in the bladder, not the Vas Deferens.